How do veins differ from arteries in terms of blood pressure?

Veins carry blood at lower pressures than arteries due to the fundamental differences in their structure and function. Arteries are thick-walled vessels designed to withstand the high pressure generated by the heart as it pumps blood throughout the body. This high pressure is necessary for the distribution of oxygen-rich blood from the heart to various tissues and organs.

In contrast, veins have thinner walls and a larger lumen, which allows them to accommodate a larger volume of blood. The blood returning to the heart has already delivered its oxygen and nutrients, resulting in a lower pressure system. Additionally, veins have valves that prevent the backflow of blood, facilitating the return of blood to the heart despite this lower pressure.

This distinction is crucial for understanding the circulatory system's dynamics and how blood is efficiently transported throughout the body. Higher pressure in arteries is necessary for effective circulation, while the lower pressure in veins ensures that blood returns to the heart in a controlled manner.